1. Field of the Invention
The present invention relates to a storage controller.
2. Description of the Related Art
A storage controller can provide large capacity storage services to a host computer (hereinafter, “host”). In a storage controller, for example, a storage area based on RAID (Redundant Array of Independent Disks) is constructed using a large number of disk drives. A logical volume (LU: Logical Unit), which is a logical storage area, is configured on the physical storage area of each disk drive. A host can read and write data from and to this logical volume.
However, a rack-mounted disk array apparatus is also known as a storage controller (Japanese Patent Laid-open No. 2005-327390). In this rack-mounted disk array apparatus, a plurality of hard disk units and interface units are replaceably disposed inside a rack installed in an enclosure. When replacing a hard disk unit, the user pulls out the hard disk unit to be replaced from the front side of the enclosure, and installs a new hard disk unit.
Further, technology for replaceably providing one hard disk drive at a time at the top and bottom of a main board is also known (Japanese Patent Laid-open No. 2004-342269).
In the above respective conventional technologies, there are disclosed storage controllers, which mount a plurality of hard disk drives inside relatively small enclosures, and which are capable of providing a RAID-based storage area. However, both of the above-mentioned conventional technologies are structured to enable the replacement of a hard disk drive. Therefore, the user can remove a hard disk drive in which a failure has occurred from the enclosure, and mount a new hard disk drive in the enclosure.
However, in recent years, due to the increasing amounts of data that must by managed by even small-scale organizations like the so-called SOHO (Small Office Home Office), demand for storage controllers has increased. In the case of large-scale users like big companies, an information technology management specialist manages the storage controller. Because a specialist has a certain degree of knowledge and skill in the construction and use of storage controllers, he can easily replace a malfunctioning hard disk drive. That is, large users can perform maintenance work on their storage controllers themselves. By contrast, small users do not have the financial wherewithal to hire specialists to manage their storage controllers, making it difficult for them to perform maintenance work on their storage controllers themselves.
However, the respective conventional technologies mentioned above are constituted to enable hard disk drives to be replaced, and rely on the user to perform storage controller maintenance, thereby lowering usability for small users, and leaving room for improvement.
Further, the above-mentioned respective conventional technologies replaceably provide a relatively small number of hard disk drives, such as two drives, inside an enclosure, without taking into account the installation of greater numbers of hard disk drives. That is, in the case of a constitution that comprises only a small number of hard disk drives, the operating noise from the respective hard disk drives is low, reducing the need for soundproofing measures. However, when a larger number of hard disk drives are mounted in an enclosure, it becomes necessary to increase the cooling capabilities of the cooling fans, and also necessitates that soundproofing measures be taken in line with this.